I am reporting a recurring problem in Adobe Acrobat Reader on Windows that seriously affects our shared-network workflow in an architectural office.

Steps to reproduce in our environment:
1. Place a PDF in a shared work folder where colleagues already have read access.
2. Open it in Acrobat Reader and digitally sign it using a digital certificate.
3. Save the signed PDF in the same location with the same filename, confirming overwrite.
4. Check the file's filesystem permissions and access from colleagues' computers.

Observed result: after signing and overwriting, the file loses the read permissions needed by colleagues. The PDF no longer appears in the shared folder from their computers. It remains available to me, so the problem can go unnoticed.

Comparison/workaround: when I save the signed PDF under a different filename, the required access permissions are retained and colleagues can see it.

Expected result: digitally signing and overwriting an existing PDF should preserve its appropriate filesystem access permissions and shared-folder access. This report concerns Windows/network file access permissions, not PDF editing or printing restrictions.

Business impact: colleagues and administrative staff assemble project documents for submission to municipal authorities. A signed document that silently becomes invisible to them can be omitted, resulting in an incomplete project submission unless I manually check every file before handover. Please investigate this as a significant reliability issue.

Additional observation, cause NOT confirmed: some PDFs received from a client by email and then downloaded into our work folder have also been inaccessible to colleagues. I do not know whether those files were signed or processed with Acrobat, or whether this has the same cause; please treat this separately from the signing/overwrite observation. I am not claiming that filesystem permissions are necessarily transmitted in an email attachment.

Environment: Adobe Acrobat Reader on Windows, shared network working folder. Exact Reader build, Windows build, server/filesystem type and before/after ACL diagnostics have not yet been documented. The underlying cause has not been independently established; please advise which diagnostics are needed to investigate permission preservation during the signed-file overwrite operation.

Thank you for investigating and correcting this issue.